Tongs of various types are commercially available in a variety of sizes and for a variety of different applications. Generally such tongs comprise either the tweezer type as might for example be utilized for philatelic purposes or the scissors type normally employed for the gripping and handling of relatively heavier items. In the photographic darkroom, tongs of both types are utilized for handling of sheet film or prints to or from developer trays or the like. For that purpose not only must the tongs be capable of grasping the sheet without distorting or marring the surface but must also be of a composition substantially resistant or inert to the processing chemicals being employed.
Most commonly employed in the photographic darkroom is the tweezer type tongs comprising a pincer-like implement formed of treated tongue depressor type wood sticks. A tweezer type tongs is exemplified by U.S. Pat. No. 1,260,302. The open or claw ends of the opposed sticks are each provided with a rubber or plastic sleeve tip having a knurled, beaded or generally abraded surface texture on the gripping faces that enhances gripping of the film or print sheets, Other available tweezer types specifically marketed for these purposes are constructed of stainless steel having a beaklike formation at the pincer end. A controlled release is provided in the event excess finger pressure is applied. Still another tong marketed for these purposes is a spring bias scissors construction with or without sleeve tips as above.
While the foregoing tong types generally function well in the photographic darkroom environment, each differs from the others in the advantages they afford and which accounts for the preferences between them among darkroom technicians. At least one serious deficiency, however, common to all of the foregoing is the associated difficulty in trying to grasp a film or print sheet after it has settled near the bottom or edge of the photographic processing tray. It will be appreciated that the relative orientation of such tongs on being hand held at a location elevated above the tray renders it most difficult to insert one end of the tongs beneath the sheet edge in order to obtain a grasp thereof.
Another drawback is the permanency of the gripping surfaces that cannot conveniently be varied to more readily accommodate different sheet surface properties and thicknesses. Moreover, the inability to interchange tip constructions can render the tongs unsuitable for use with certain chemical contacts thereby severely restricting use of the tongs to only those specific applications with which they are strictly compatible.
Despite recognition of the foregoing problems, a ready solution therefor has not heretofore been known.